Targeted Grazing Research

Below are some of the various articles, case studies, research reports, and other publications regarding aspects of targeted grazing. If you have any additional resources to share or a report to add to the list, send to Margaret at support@goatsonthego.com.

General Brush and Vegetation Management, invasive management, etc

Brush Management with Goats - Iowa NRCS (IA). Describes brush grazing as a conservation practice, including NRCS standards of % leaf removal, stocking density, etc.

Use of Goats for Sustainable Vegetation Management in Grazing Lands - SARE (OK). Two-year project looking at grazing preferences of goats and goat performance. Goats maintained condition and parasite load was low in goats ‘grazing up.’ Goats reduced prevalence and vigor of many invasive/nuisance brushy/woody and ‘weed’ species. EXCELLENT literature review.

Economic and Environmental Impacts of Invasive Species and Their Management - David Pimentel (USA). The first page contains some statistics on the extent (acres) or expense/cost ($) of invasive species for farmers and the overall economy.

The Effectiveness of Using Targeted Grazing for Vegetation Management: A Meta-Analysis - Marchetto et al (USA, some worldwide). Analysis of existing research on targeted grazing management, across many climates, locations, vegetation, and animal species. Main findings: grazing can and often does reduce the proportion of undesirable species and increases species diversity; however, the longer-term effects (i.e. are those plants weakened or killed?) is rarely documented, and the detail of the species diversity (i.e. are the new plants natives or other invasives/non-natives?) isn’t often considered. Great resource for finding further reading.

Potential for Using Goats as a Vegetation Management Tool for Enhancing Landfill Cap Stability and Reducing Maintenance Costs - Ison and Hutchens (KY). While the specific instance was a landfill cap, the paper also includes a basic business analysis and economics, and animal and nutrient management concerns.

Meat Goats in Land and Forage Management - Leginbuhl et al (NC). Great overview of the effects of goat grazing on brush and weed species prevalence in pastures, woodlands, etc. as well as animal performance concerns.

Goats as Grazing Animals for Invasive Plant Management 2005-2006 - Nature Conservancy (NY). Study on goat grazing including changes in % cover of different species before and after grazing.

Biological Weed Control - Using Goats to Control Noxious Weeds - Banks (UT). In this short-term and very small study, goats were actually more expensive and less effective compared to herbicide (on the weed species investigated - note not brush), but the author includes some good considerations and recommendations for deploying goats.

Quantifying Nutritional Value and Best Practices for Woody Fodder Management in Ruminant Grazing Systems - SARE (NY). Still in progress but final report should be available in 2022. Main output will be information on nutritional content of woody plants and trees throughout the year, as well as insights on how to incorporate fodder into a grazing system.

Vitamin E in Invasive Vegetation - Wilmoth (WV). Vit E content in was greatest in autumn olive, then bush honeysuckle, and then multiflora rose. Vit E increases throughout the growing season, generally increases during fruit ripening, and can often increase during drought or other stress periods.

Interactions Between White-tailed Deer and Invasive Plants in North American Forests - Martinod and Gorchov (OH). The presence of an invasive species (in this case bush honeysuckle) with a longer green leafy period, may be harmful to native bushes and shrubs because it allows for a greater natural deer stocking density. Deer preferred the still-green leaves of honeysuckle to already-dead twigs of native species during early winter and early spring, but then switched to native species once they leafed out.

The Establishment of Native Plant Species for Livestock Forage and Wildlife Habitat in Silvopasture Systems - SARE (MO). Project still in progress - overall goal is identifying ways to combine silvopasture and haying/grazing, as well as use of tree fodders as livestock feed (nutritional values will be determined). There’s mention of integrating pollinator habitat - hopefully this will be useful when recommending new species to plant for grazing customers.

Browse by White-tailed Deer Decreases Cover and Growth of the Invasive Shrub, Lonicera maackii - Peebles-Spencer et al (link coming soon)

Species-specific control and research

Control of Autumn Olive, Multiflora Rose, and Tartarian Honeysuckle - Darlington and Loyd (WV). Description and identification of the species, growth habits, contributions to wildlife, and control methods. Specifically they recommend repeated defoliations early in the growing season.

Eliminating Invasive Buckthorn with Goats, An Ecological and Habitat Restoration Study - SARE (WI). Grazing alone (repeated grazing as brush regrew) was compared to cutting followed by goat grazing when it regrew to about knee height. Buckthorn regrew as fast post-grazing as it did post-cutting, but the ‘structure’ and height were lower for cutting. Cutting eliminates the canopy faster and reduces overall brush height more quickly, but requires a lot more labor, and oftentimes triggers an explosion of new seedlings to grow - almost making grazing mandatory to prevent the area from being re-invaded in a hurry. A few ideas are mentioned on how to work out a reasonable/feasible management system.

Goat Digestion Leads to Low Survival and Viability of Common Buckthorn (Rhamnus cathartica) Seeds - Marchetto et al (MN). Goats were fed buckthorn seeds, after which feces were checked for seeds and the seeds were checked for viability. Only 2% of seeds made it into the feces intact, and only 11% of those were viable. When looking at other research, the current ‘rule of thumb’ is that seeds >4mm long are unlikely to make it through the goat GI system intact.

Value of Goats as a Mechanism for Eliminating Lespedeza cuneata from a Restored Tallgrass Prairie - Klodd et al (IA). Goat grazing reduced the height and density of lespedeza vs ungrazed areas, including the portions that would later produce seeds.

nrcs / eqip information

In some states, targeted grazing like we provide is a cost-shared practice. The name varies: “biological brush control” and “prescribed grazing” seem to be the most common.

This map lets you look up each state’s current year payment rates for different practices. EQIP practices and payment rates are updated annually. Clicking on a state brings you to a summary of the programs - look for EQIP. In that spreadsheet, look for practices 314 (brush management), 315 (herbaceous weed management), and 528 (prescribed grazing).

Ultimately, whether a practice is funded in your area is set by the state and additionally by the county. You will need to check with your local NRCS office to see whether it’s a funding option, and to see what the standards and requirements are.

Iowa has a very detailed and descriptive set of practice standards (search for practice 528-8).